1. Field of the Invention
The present invention relates to a type of X-ray film processor, herein called an automated static X-ray film processor, that, in order to process X-ray film, moves chemicals into and out of one of a plurality of reaction chambers. More specifically, the present invention relates to an automated static X-ray film processor that will allow for an operator to start a film processing cycle in one reaction chamber while a previous cycle has already started and is running in another reaction chamber.
2. Prior Art
Around 1900 radiographs were just starting to be utilized in the medical, dental, veterinary, and other health related fields. This new X-ray technology greatly aided the health practitioner in diagnosing disease and injury of the hard tissues. In more recent years, radiographs, with the aid of other diagnostic techniques, have been helpful in soft tissue diagnosis.
For over sixty years exposed radiographic film has been exclusively hand developed in a darkroom. That is, in a darkroom, the film was uncovered under protective red light, then placed in developer solution, then washed, then placed in fixer solution, then washed, and then air-dried. The deficiency of manual processing is that it is very time consuming and inefficient.
In the 1970""s an automated roller transport film processor was brought to market. As of this writing, roller processors are still the most common types of processor sold. This type of processor is composed of four roller racks configured one in front of the other. When x-ray film is placed in the processor, the rollers pick up the film and transport it through a series of open tanks that contain processing chemicals. X-rays are moved through developer chemical, then fixer chemical, then a water wash, and finally through a dryer area. Variations have been introduced on the roller processor model. One such variation is a type of developer that uses a nylon gauze-like material configured so that it sandwiches the film, and thereby similarly transports it through the same series of tanks and chemicals as a roller processor. Other types of processors have been marketed which use other types of transport devices, all of which use a system that moves film from one end of the processor to the other. There are several inherent deficiencies with these types of transport processors that detract from their utility. Frequently, film falls out of the transport systems and becomes lost in one of the storage tanks. The result is damaged or destroyed X-ray film. Additionally, because transport mechanisms are constantly immersed in chemical, deposits collect thereon, in turn causing the film to be scratched and damaged. Transport processors require an inordinate amount of maintenance in order to remove scum that collects on the transport mechanisms. Additionally, transport processors do not process film in patient identified groups. There is no efficient way of identifying the X-rays by patient. The result is that films from one patient can be mixed up with films from another, exposing the patient to the danger of misdiagnosis. To alleviate these and.other deficiencies, several inventors have designed and patented processors that have a single reaction chamber. Chemicals, wash water, and dryer air move into and out of this single reaction chamber. X-ray films, once placed inside, remains stationary or static therein. For the sake of this writing, this type of processor shall be designated automated static X-ray film processor. There are many advantages to this type of processor. Because X-ray films do not touch a transport device, films are not scratched, jammed, stuck together, or lost. The resultant film quality is far superior. There are no mechanisms being immersed in chemical and collecting deposits, thus substantially eliminating the need for maintenance. X-ray films are always in one location, which means the X-ray films can never be lost. Because X-ray films are batch processed, patient identity is easily accomplished. X-ray films will not be misidentified nor mixed up.
There are currently several patents that describe automated static film processors. Anthony R. Peres (U.S. Pat. No. 3,792,487) describes an automatic film processor system that has temperature-controlled containers for storing chemicals, and he claims xe2x80x9ca film holding chamber belowxe2x80x9d. Dennis C. Rebek (U.S. Pat. No. 4,054,902) describes an apparatus for developing photographic prints including a cabinet, which houses a developing tank. Heinrich Huss (U.S. Pat. No. 3,890,629) describes a device for developing photographic film with a tank containing a drum arranged for immersing the film in developing chemicals. Lasky and Wright (U.S. Pat. No. 4,097,884) describe an apparatus for processing X-ray film comprising a processing tank with valves for developing solutions and water. Wada and Ishikawa (U.S. Pat. No. 4,134,665) describe a single bath- type developing device. Stephen Blume (U.S. Pat. No. 5,235,372) describes developer and fixer reservoirs fluidly connected to a single reaction chamber. Theodore Perl (U.S. Pat. No. 3,727,533) describes a small X-ray developer where films are dropped into a developing tank. M. Mastrosimone et al (U.S. Pat. No. 3,437,030) claims a processor with a container and a means to move developer chemicals into and out of said container.
The key deficiency of static film processors is the fact that it is not possible for an operator to begin processing a second set of films once a previous set has been started and is still running. Because of this fact, static film processors are ergonomically very inefficient. The operator must wait until the first set of X-ray films is completed before a second set can be placed inside for processing.
In order to alleviate this multiple cycle deficiency, Blume Imaging, a California LLC, manufactured and sold a static film processor with a horizontal rotating lid. An exposed set of X-ray films were placed on a cassette, then attached to the lid via an attachment device. When the start key was pressed, the lid would rotate 180 degrees, moving the X-ray films down into the reaction chamber. A new upper vacant side was now available for a second set of X-ray films to be attached. A second operator would place X-ray films on a cassette, then attach the cassette to the upper lid surface via an attachment device. The X-ray films in the reaction chamber were developed, then washed, then dried. Once the primary cycle was complete, the lid would rotate the processed film up, and the second set of films down into the reaction chamber for processing. Once the processed first cycle set of films was removed from the lid, the now vacant upper lid would be ready for another set of exposed X-ray films to be attached. This early solution to the second cycle deficiency of automated static X-ray film processors proved successful, but required complex mechanics and electronics, raising the per unit cost of the processor. Assembly was also complicated. Additionally, the radius required to rotate the film into the reaction chamber made the outer dimensions of the processor quite large, which proved to be another deficiency. Further, cycles ran consecutively rather than successive but overlapped. That is, a secondary cycle cannot run while a primary cycle is running. The result is that this design is xe2x80x9ctime inefficient.xe2x80x9d Two seven-minute cycles would take at least fourteen minutes to process.
DXSS Inc., a company from the state of Washington, produces a static film processor with a single reaction chamber and a xe2x80x9cwaitingxe2x80x9d black box which serves as a holding station for the next film group. If a first set of X-ray films are already processing, a second operator may uncover a previously exposed set of films and place them in the black box with lid. This black box is light proof, and will not allow film to be damaged. A flashing indicator light shows that X-ray films are inside, ready for processing. When a first operator removes a completed set of films from a first cycle, that first operator will place the set of films from the black box in the processor, and start another developing cycle, thus producing a xe2x80x9cpseudoxe2x80x9d second cycle. This solution is simple, but time consuming and inefficient. Because cycles run consecutively, a second cycle may not be completed for over fifteen minutes, interrupting the ergonomic flow of the facility. And, the possibility of error by a second operator handling the exposed X-ray films, or neglecting to place the black box film in the processor further complicates matters. The DXSS design has its own set of deficiencies.
Clearly, there must be an improvement in the design of static automated film processors. No static processor design is known that will simply and efficiently allow the running of a second cycle while a first cycle has already started. Transport processors allow operators to continually feed film in making transport processors more ergonomically efficient than all known static automatic film processor designs. Without such an improvement, automated static film processors cannot be commercially successful.
In accordance with a preferred embodiment of the present invention there is provided a plurality of X-ray film cassettes which hold X-ray films during manipulation, and an automated static X-ray film processor comprising a housing defining first and second reservoirs which are capable of storing quantities of developer and fixative agents therein. The housing further includes two or more reaction chambers, each defining a front, back, and side walls, a lower surface, and an upper rim with lid. The lid is capable of being open when X-ray films are being inserted or removed from the reaction chamber, and closed to prevent light damage to X-ray films once processing has begun. Each reaction chamber is sized and configured to receive a plurality of X-ray film cassettes with intra-oral film. Further, each reaction chamber is sized to receive cassettes that hold panographic (12xe2x80x3xc3x976xe2x80x3) and cephalometric (8xe2x80x3xc3x9710xe2x80x3) extra-oral film combined with intra-oral X-ray films as required. The reaction chambers and reservoirs are to be constructed of a chemically inert material such as plastic, stainless steel, or the like, to prevent severe corrosion that would be caused by developer and fixer chemicals, and are fluidly sealed to hold a quantity of water and chemical.
The developer storage reservoir and fixer storage reservoir fluidly communicate via respective feed lines or conduits to each of a plurality of reaction chambers, thereby allowing the flow of chemicals from developer storage and fixer storage reservoirs to reaction chambers and back. Disposed between each feed line and reaction chamber is a manifold with valves utilized for the organized and sequential flow of water and chemicals into and out of the reaction chambers. Each manifold has mounted thereon developer, fixer, and drain valves. The developer and fixer valves are operable to selectively place a respective developer or fixer storage reservoir in fluid communication with each of the reaction chambers. Preferably, each of the feed lines with manifold and valves connecting the developer storage reservoir and fixer storage reservoir to each reaction chamber are fluidly coupled to a point adjacent to the lower surface of the reaction chambers. Fluidly coupled to and extending from each reaction chamber manifold adjacent to the lower surface thereof is a drain line, which includes said drain valve coupled therein for selectively opening and closing each drain line. Each reaction chamber manifold further includes one or more water filler hoses fluidly coupled thereto which are connected to an incoming water source and used to selectively fill each reaction chamber with water, thereby rinsing each reaction chamber and the X-ray films therein.
Additionally, each feed line is configured so that it is in communication with one or more selected first force means which is capable of moving chemical from the developer storage reservoir and fixer storage reservoir into each reaction chamber. The selected first force means may be one or more means of the group consisting of: a pump, air pressure, gravitational force, and vacuum. Further, each feed line is configured so that it is in communication with a selected second force means, which is capable, of moving chemical back into the developer storage reservoir and fixer storage reservoir. The second force means may be one or more means of the group consisting of: a pump, air pressure, gravitational force, and vacuum. Also, fluidly coupled to each reaction chamber adjacent to the upper rim is an overflow line configured to prevent flooding if a malfunction of the water or developer or fixer valves occurs. The overflow pipe should have large enough lumen to rapidly drain off liquids and prevent overflowing for a long period of time should there be a valve failure. Additionally, each reaction chamber includes a duct disposed to allow the inflow of warm air from a heater/blower mechanism for the purpose of drying X-ray films once a final wash cycle is completed.
In accordance with the preferred embodiment, the front walls of the reaction chambers are oriented in a manner complimentary to the shape of the intra-oral X-ray film cassettes and/or larger extra-oral X-ray film rack. Additionally, the distance separating the front and back walls of the reaction chambers (i.e., the width of the side walls) is dimensioned so as to slightly exceed the width of the film-holding cassettes and films, and no more, the purpose being to utilize the least amount of chemical possible. Further, the height of the reaction chambers should be just enough to allow a thorough submerging of the X-ray films (at least xc2xd to 1 inch) plus an additional height that will resist the overflow of chemicals or water. Further, the height of the reaction chamber should be sufficient to allow for the placement of the overflow pipe above the maximum height of the water level in the reaction chamber. Configured adjacent to the upper rim of each reaction chamber is a water sensor, capable of signaling a controller that water has reached said water sensor. X-ray film cassettes and large film holders are configured to be attachable or supportable by the rim of each reaction chamber so that the X-ray films do not touch the chamber bottom or sides during processing. In this respect the upper part of the film holding cassettes and large film holder is supported by the upper rim of the reaction chambers so that X-ray films will be totally immersed in chemistry solutions sequentially applied therein. Additionally, there is configured an electronic controller with keypad, electronically coupled with all electric control devices, valves, dryers, and the like, related to the automated static X-ray film processor. Said electronic controller being capable of selectively operating said electric control devices in a pre-programmed manner that will allow for the processing of X-ray films in reaction chamber therein. For the purposes of this writing, the term primary cycle will denote a cycle in any reaction tank that is started ahead of all other cycles in operation. A secondary cycle will be a processing cycle that is started after the start of a primary cycle. Additionally, when the terms xe2x80x9cfilmsxe2x80x9d or xe2x80x9cset of filmsxe2x80x9d are utilized, they shall denote one or a plurality of individual films.
In operation of the automated static X-ray film processor of the present invention, a primary operator exposes a set of X-ray films on a patient in an operatory. The exposed X-ray films are taken to a darkroom, or placed in a daylight-loading device attached to the processor, where they are uncovered then mounted on a film holding device or cassette. The films with cassettes are then placed in an available reaction chamber. The lid of the reaction chamber is closed, and the start key for that chamber is pressed on the electronic controller panel. As soon as the primary cycle commences in the chosen reaction chamber, a secondary operator who has already exposed X-ray films on another patient may now uncover the X-ray films and place them in an available secondary reaction chamber, and press the associated start key. The second set of films will remain in waiting in the secondary reaction chamber until the fixer chemical portion of the primary cycle in the primary reaction chamber is complete, making chemicals available for the secondary cycle. The secondary cycle will commence in the secondary reaction chamber as soon as the fixer chemical is returned to the fixer storage reservoir from the primary reaction chamber. Or, if the fixer portion of the primary cycle is complete and the set of X-ray films in the primary reaction chamber is in final washing and drying, the secondary cycle may start immediately in the secondary reaction chamber.
In the preferred embodiment, the developing cycle in the primary reaction chamber proceeds as follows: the valve disposed between the developer storage reservoir and the primary reaction chamber is electronically opened via the electronic controller and first force means is activated which forces developer chemical to flow into the primary is reaction chamber and begin the developing process. Once the X-ray films are properly developed, an electronic signal is sent via the electronic controller which causes developer chemical to return to the developer storage reservoir via second force means. The associated developer valve is signaled to close via the electronic controller, trapping the developer chemical therein. A water wash is then initiated. The water valve associated with the primary reaction chamber is signaled to open via the electronic controller, which fills the primary reaction chamber with water. Water inflow is terminated when it reaches the water sensor in close proximity to the top of the primary reaction chamber. The water sensor is configured above the highest level that chemicals reach to insure a thorough removal of remnant chemical. Additionally, the water sensor is configured so that the X-ray films therein are thoroughly submerged with water so that a complete wash is accomplished. Once water touches the water sensor, the associated primary reaction chamber water valve is electronically signaled to close via the electronic controller, and the associated drain valve is electronically opened. Wash water is thereby drained from the primary reaction chamber. Once all wash water is removed from the primary reaction chamber, the associated drain valve is signaled to close via the electronic controller. Next, the valve disposed between the fixer storage reservoir and the primary reaction chamber is electronically signaled to open via the electronic controller and a first force means is activated which forces fixer chemical to flow into the primary reaction chamber and begin the fixing process. Once the X-ray film is property fixed, the electronic controller signals, causing the fixer chemical to return to the fixer storage reservoir via second force means and the associated valve is closed, trapping the fixer chemical therein. At this time in the primary cycle, chemicals are available for use in the secondary reaction chamber, and a processing cycle in the secondary reaction chamber may commence.
X-ray films in the primary reaction chamber are now washed, as described above. A drying function initiated by the electronic controller now commences, whereat warm air is blown on the X-ray films from a blower and heater coil mechanism. Once the X-ray films are dried, the primary processing cycle is completed. The X-ray films are removed from the primary reaction chamber, another set of exposed X-ray films may be placed therein, and another developing cycle begun while X-ray films are processing in the secondary (now primary) reaction chamber; and on and on. Processing proceeds in the new primary reaction chamber in the same manner as described above for the previous primary reaction chamber.